US4027951AExpiredUtilityPatentIndex 63
Parfocal low-magnification microscope objective lens systems
Est. expiryOct 19, 1994(expired)· nominal 20-yr term from priority
G02B 21/02
63
PatentIndex Score
7
Cited by
2
References
4
Claims
Abstract
A parfocal low-magnification microscope objective lens system comprises, in succession from the object side, a positive first lens member, a negative second lens member and a positive third lens member. The first lens member has its concave surface facing the object; the second lens member includes at least one negative meniscus lens component with its concave surface facing the object; and the third lens member includes a positive lens component with that surface thereof sharper in radius of curvature facing the image plane side. The lens system satisfies the following four conditions: d A <f A <d A + |f B |; d A <d B ; |f B |<|f A |; and |d B |>|f B |; where f A and f B are the focal lengths of the first and the second lens member, respectively, d A is the distance from the rear principal plane of the first lens member to the front principal plane of the second lens member, and d B is the distance from the rear principal plane of the second lens member to the front principal plane of the third lens member.
Claims
exact text as granted — not AI-modifiedWe claim:
1. A parfocal low-magnification microscope objective lens system comprising: a positive first lens member disposed at a position nearest to the object and with its convex surface facing the object; a negative second lens member disposed at a position farther from said object than said first lens member and including at least one negative meniscus lens component having its convex surface facing the object side; and a third positive lens member disposed at a position farthest from said object and including a positive lens component with that surface thereof sharper in radius of curvature facing the image plane side; said lens system satisfying the following four conditions: d.sub.A< f.sub.A < d.sub.A +| f.sub.Z| ( 1) d.sub.A < d.sub.B ( 2), |f.sub.B|<| f.sub.A| ( 3), ↑d.sub.B|<| f.sub.B| ( 4), where f A is the composite focal length of the first lens member, f B is the composite focal length of the second lens member, d A is a rear focal plane of the first lens member to front focal plane of the second lens member distance, and d B is a rear focal plane of the second lens member to front focal plane of the third lens member distance, the parameters of said system having the following values: ______________________________________
WD= 5.5
1st R.sub.1 = 14.8
member d.sub.1 = 2.2
n.sub.1 = 1.58913
νd.sub.1 = 61.2
(A) R.sub.2 = -600.0
d.sub.2 = 13.1
R.sub.3 = 45.0
2nd d.sub.3 = 3.0
n.sub.2 = 1.74077
νd.sub.2 = 27.7
member R.sub.4 = -16.0
(B) d.sub.4 = 0.5
n.sub.3 = 1.713
νd.sub.3 = 53.9
R.sub.5 = 5.487
d.sub.5 = 16.7
R.sub.6 = -54.8
d.sub.6 = 2.8
n.sub.4 = 1.51823
νd.sub.4 = 59.0
R.sub.7 = -12.7
3rd d.sub.7 = 0.1
member R.sub.8 = 360.0
(C) d.sub.8 = 1.0
n.sub.5 = 1.7495
νd.sub.5 = 35.0
R.sub.9 = 18.85
d.sub.9 = 3.1
n.sub.6 = 1.50032
νd.sub.6 = 81.9
R.sub.10 = -20.38
______________________________________
wherein R 1 , R 2 , . . . . are the radii of curvature of the individual surfaces, d 1 , d 2 . . . . are the axial thickness or spacing of the individual elements, WD is the axial distance from the object to the first surface of the lens system, n 1 , n 2 . . . . are the refractive indexes of the individual elements and νd 1 , νd 2 , . . . . are the Abbe numbers of the individual elements.
2. A parfocal low-magnitication microscope objective lens system comprising: a positive first lens member disposed at a position nearest to the object and with its convex surface facing the object; a negative second lens member disposed at a position farther from said object than said first lens member and including at least one negative meniscus lens component having its convex surface facing the object side; and a third positive lens member disposed at a position farthest from said object and including a positive lens component with that surface thereof sharper in radius of curvature facing the image plane side; said lens system satisfying the following four conditions: d.sub.A < f.sub.A< d.sub.A +| f.sub.B| ( 1), d.sub.A < d.sub.B ( 2), |f.sub.b|<| f.sub.A| ( 3), |d.sub.B|< f.sub.B| ( 4), where f A is the composite focal length of the first lens member, f B is the composite focal length of the second lens member, d A is a rear focal plane of the first lens member to front focal plane of the second lens member distance, and d B is a rear focal of the second lens member to front focal plane of the third lens member distance, the parameters of said system having the following values: __________________________________________________________________________
WD = 4.0
1st R.sub.1
= 17.0
member d.sub.1
= 2.5 n.sub.1 = 1.65128
νd.sub.1 = 38.3
(A) R.sub.2
= -95.5
d.sub.2
= 10.0
R.sub.3
= 18.1
d.sub.3
= 2.5 n.sub.2 = 1.76182
νd.sub.2 = 26.5
R.sub.4
= -21.2
2nd d.sub.4
= 0.8 n.sub.3 = 1.51823
νd.sub.3 = 59.0
member R.sub.5
= 4.62
(B) d.sub.5
= 4.0
R.sub.6
= -7.956
d.sub.6
= 2.0 n.sub.4 = 1.7495
νd.sub.4 = 35.0
R.sub.7
= -20.8
d.sub. 7
= 14.5
R.sub.8
= -53.1
d.sub.8
= 3.5 n.sub.5 = 1.58894
νd.sub.5 = 61.04
R.sub.9
= -16.559
3rd d.sub.9
= 0.3
member R.sub.10
= 70.1
(C) d.sub.10
= 1.4 n.sub.6 = 1.71736
νd.sub.6 = 29.5
R.sub.11
= 21.0
d.sub.11
= 3.3 n.sub.7 = 1.50032
νd.sub.7 = 81.9
R.sub.12
= - 26.584
__________________________________________________________________________
where R 1 , R 2 , . . . are the radius of curvature of the individual surfaces, d 1 , d 2 . .. . are the axial thickness or spacing of the individual elements, WD is the axial distance from the object to the first surface of the lens system, n 1 , n 2 , . . . are the refractive indexes of the individual elements and νd 1 , νd 2 , . . . are the Abbe numbers of individual elements.
3. A parfocal low-magnification microscope objective lens system comprising: a positive first lens member disposed at a position nearest to the object and with its convex surface facing the object; a negative second lens member disposed at a position farther from said object than said first lens member and including at least one negative meniscus lens component having its convex surface facing the object side; and a third positive lens member disposed at a position farthest from said object and including a positive lens component with that surface thereof sharper in radius of curvature facing the image plane side; said lens system satisfying the following four conditions: d.sub.A< f.sub.A < d.sub.A +| f.sub.B| ( 1), d.sub.A < d.sub.B ( 2), |f.sub.B|<| f.sub.A| ( 3), ↑d.sub.B|<| f.sub.B| ( 4) where f A is the composite focal length of the first lens member, f B is the composite focal length of the second lens member, d A is a rear focal plane of the first lens member to front focal plane of the second lens member distance, and d B is a rear focal plane of the second lens member to front focal plane of the third lens member distance, the parameters of said system having the following values: __________________________________________________________________________
WD = 2.0
R.sub.1
= 16.3
d.sub.1
= 2.9 n.sub.1 = 1.713
νd.sub.1 = 53.9
1st R.sub.2
= 74.0
member d.sub.2
= 0.2
(A) R.sub.3
= 17.0
d.sub.3
= 1.7 n.sub.2 = 1.62004
νd.sub.2 = 36.3
R.sub.4
= 24.0
d.sub.4
= 8.8
R.sub.5
= 27.0
d.sub.5
= 2.4 n.sub.3 = 1.76182
νd.sub.3 = 26.5
R.sub.6
= -8.0
2nd d.sub.6
= 0.8 n.sub.4 = 1.74443
νd.sub.4 = 49.4
member R.sub.7
= 5.72
(B) d.sub.7
= 7.8
R.sub.8
= -5.03
d.sub.8
= 1.0 n.sub.5 = 1.74443
νd.sub.5 = 49.4
R.sub.9
= -27.0
d.sub.9
= 15.2
R.sub.10
= -110.0
d.sub.10
= 0.8 n.sub.6 = 1.7495
νd.sub.6 = 35.0
R.sub.11
= 27.84
d.sub.11
= 2.1 n.sub.7 = 1.58894
νd.sub.7 = 61.04
3rd R.sub.12
= -17.335
member d.sub.12
= 0.2
(C) R.sub.13
= 51.0
d.sub.13
= 0.8 n.sub.8 = 1.67163
νd.sub.8 = 38.8
R.sub.14
= 25.3
d.sub.14
= 2.2 n.sub.9 = 1.50032
νd.sub.9 = 81.9
R.sub.15
= -24.419
__________________________________________________________________________
where R 1 , R 2 , . . . are the radii of curvature of the individual surfaces, d 1 , d 2 , . . . are the axial thickness or spacing of the individual elements, WD is the axial distance from the object to the first surface of the lens system, n 1 , n 2 , . . . . are the refractive indexes of the individual elements and νd 1 , ∥d 2 , . . . are the Abbe numbers of individual elements.
4. A parfocal low-magnification microscope objective lens system comprising: a positive first lens member disposed at a position nearest to the object and with its convex surface facing the object; a negative second lens member disposed at a position farther from said object than said first lens member and including at least one negative meniscus lens component having its convex surface facing the object side; and a third positive lens member disposed at a position farthest from said object and including a positive lens component with that surface thereof sharper in radius of curvature facing the image plane side; said lens system satisfying the following four conditions: d.sub.A< f.sub.A< d.sub.A +| f.sub.B| ( 1), d.sub.A< d.sub.B ( 2), |f.sub.B|<| f.sub.A| ( 3), |d.sub.B|˜|< f.sub.B|( 4), where f A is the composite focal length of the first lens member, f B is the composite focal length of the second lens member, d A is a rear focal plane of the first lens member to front focal plane of the second lens member distance, and d B is a rear focal plane of the second lens member to front focal plane of the third lens member distance, the parameters of said system having the following values: __________________________________________________________________________
WD = 2.1
R.sub.1
= 26.3
d.sub.1
= 3.2 n.sub.1 = 1.6228
νd.sub.1 = 56.9
R.sub.2
= -320.0
1st d.sub.2
= 0.1
member R.sub.3
= 14.2
(A) d.sub.3
= 2.2 n.sub.2 = 1.62041
νd.sub.2 = 60.3
R.sub.4
= 21.0
d.sub.4
= 15.0
R.sub.5
= 21.0
d.sub.5
= 1.5 n.sub.3 = 1.7552
νd.sub.3 = 27.5
R.sub.6
= -9.0
2nd d.sub.6
= 0.7 n.sub.4 = 1.713
νd.sub.4 = 53.9
member R.sub.7
= 9.0
(B) d.sub.7
= 0.5
R.sub.8
= -9.0
d.sub.8
= 0.8 n.sub.5 = 1.713
νd.sub.5 = 53.9
R.sub.9
= 4.6
d.sub.9
= 16.5
R.sub.10
= -51.0
d.sub.10
= 2.0 n.sub.6 = 1.62374
νd.sub.6 = 47.0
R.sub.11
= -13.32
3rd d.sub.11
= 0.1
member R.sub.12
= 105.0
(C) d.sub.12
= 0.6 n.sub.7 = 1.74
νd.sub.7 = 28.2
R.sub.13
= 17.0
d.sub.13
= 3.2 n.sub.8 = 1.50032
νd.sub.8 = 81.9
R.sub.14
= -20.28
__________________________________________________________________________
where R 1 , R 2 , . . . are the radii of curvature of the individual surfaces, d 1 , d 2 , . . . are the axial thickness or spacing of individual elements, WD is the axial distance from the object to the first surface of the lens system, n 1 , n 2 , . . . are the refractive indexes of the individual elements and νd 1 , νd 2 , . . . are the Abbe numbers of individual elements.Cited by (0)
No later patents cite this yet.
References (0)
No backward citations on record.